Ola y muchas gracias @froldan!
Your timely list of report related bugs - plagiarized here from the Telegram dev channel - makes a solid case for additional tests IMHO.
For QA (quality assurance), up to now ERPNext has relied on just two report tests!?
General Ledger
[BUG] General Ledger Group by Voucher not ordering by posting_date · Issue #17707 · frappe/erpnext · GitHub
Multicurrency issues and account
Returned invoices without against voucher no are not showing in Account Receivable and Payable report · Issue #16879 · frappe/erpnext · GitHub
Credit Note adjustment, without any Payment · Issue #16697 · frappe/erpnext · GitHub
Can’t reconcile multi-currency invoice with multi-currency payment · Issue #15174 · frappe/erpnext · GitHub
[BUG]Multi currency error · Issue #15398 · frappe/erpnext · GitHub
[Bug] Payment Entry - Exchange Rate Issue · Issue #17553 · frappe/erpnext · GitHub
Credit note to be shown in Payment Reconciliation · Issue #17248 · frappe/erpnext · GitHub
Credit notes and payment reconciliation · Issue #17417 · frappe/erpnext · GitHub
Reports
[bug] Campaign Efficiency report only works in english · Issue #17282 · frappe/erpnext · GitHub
[Bug] Preparing Report progress bar and required filters · Issue #17584 · frappe/erpnext · GitHub
[BUG] General Ledger Group by Voucher not ordering by posting_date · Issue #17707 · frappe/erpnext · GitHub
perf: Asset Depreciations and Balances report by Don-Leopardo · Pull Request #17421 · frappe/erpnext · GitHub
Report builder
[bug] Multiples issues in report builder · Issue #14803 · frappe/frappe · GitHub